Exhaust-manifold.



0.,5. KlRKHAMf EXHAUST MANIFOLD:

APPLICATION FILED MAR. 26. 1917 1,294,475 Patented Feb. 18, 1919. I

5145mm CHARLES EIKIEPJKHAM CHARLES B. KIRKHAM, 0F BUF ALO; NEW YORK, AssIGNoR r0 CURTISS AERorLANE AND MOTOR CORPORATION, A CORPORATION OF NEW YORK.

EXHAUST-MANIFOLD. j

To all whom it may concern.

Be it known that I,'CHARLEs1B. KIRK- HAM, a citizen of the United States, reside ing at Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Exhausttors are of such Construction that they offer quite an appreciable resistance to the free passage of the exhaust gases through them.

This resistance is due in a large measure.

to the skin friction which produces a choking of the gases exhausted from the cylinders,together with abnormal back pressure and a resulting loss of power which is ex tremely undesirable, particularly in the case of motors which are used in connection with aeronautical workfwhere maximum power 'output with minimum. weight is of extreme importance. 1

. 11 order to overcome the above mentioned objections Iprovide a manifold in'which all the conduits forming a part of. the manifold are of expanding cross sectional area throughout their length from the inlet to the outlet. In this way the exhaust gases are free to expand as they traverse the length of the conduit thereby greatly,reducing the back pressure which would otherwise result from excessive pipe friction.

In addition to provldingexpandingconduits throughout in the construction ofmy manifold the main conduit and the several branches which lead therefrom and connect with the separate exhaust ports of the motor cylinders are so arranged that they present quite an appreciable influence in the exhausting of any particular cylinder by reason of the fact that the suction created -by the passage of exhaust gases from one cylinder draws the exhaust gases from the succeedingly firing cylinders into the main conduit. Thus it is seen that my invention not only overcomes the objections of back pressure but it also actually induces a more complete exhaustion of the gases from the cylinders.

' Application filed March 26, 1917. Serial No. 157,452.

Specification of Letters Patent. Patented Feb. 18, 1919. 1

More particular reference may be'hadto the accompanying drawings, in whichz/ Figure 1 is an elevation of an airplane upon which my manifold is mounted."

Fig. 2 is a longitudinal section through themanifold of my invention.

Fig. 3 is aplan viewof the manifold. Y Fig.' 1, is a lateral section through a portion of themanifold.-

. In Fig. l the manifold may-be represented as comprising a series of inletcdnduits 1, 2, 3 and 4, which are designed to connect with the various cylinders of an-internal .UNITEDISTATES PATENT orries. l-

combustion engine. The'main body ofthe, .manifold, represented as an entirety by 5 is composed of an outer conduit casing 6 to which are connected the branches 1 and 4, and an, inner conduit casing 7 to \WhlCh are connected the conduits 2 and 3. This may be more clearly understood by reference toFig. 3 in which the exact relation of .the conduits6 and 7 is clearly shown. Both. these conduits 6 and '7 are provided with a common outlet 8 which is arranged for connection wlth an exhaust pipe or suitable muffler as desired. It will be noticed that the main conduit casings ,both inner and outer, as well as the branches which lead therefrom are ofconstantly expanding cross sectional area for the reasonspointed out in the first part of the specification.

In order for the manifold to operate to the best advantage the firing order of the cylinders in the case of four cylinders exhausting into the manifold should be 1, 2,

4, 3, although several other combinations of firing order may be used, depending on the cylinder arrangement and the arrange "'ment of the branches relativeto the main conduits. Assuming, however,.that the firing order is 1, 2', 4., 3,..it may easily be seenthat the cylinder exhausting into' conduit No. 1 will force its gases out-through the outer conduit-casing 6. 'The exit of these gases-from the mouth" of the casing t5 into the common outlet 8 produces a suction within the conduit 7. Cylinder-No. 52 which fires next is therefore assisted in exhausting by reason ofthis suction. In the same manner as above set forth the action of the gases issuing from the mouth of the inner conduit 7 into the common outlet 8 will pro duce "a suction in the outer-conduit 6 ,Whereupon the exhaust gases created by the firing of-cyl'inder N0. 4: are drawn out. The action of the gases escaping from the conduit (3 as they pass into the common .outlet 8 will again produce suction in the conduit 7 thereby assisting in theexhau'st of the gases created by the firing of cylinder No. 3.

Branches 1, 2, 3 and i of the manifold are provided with reinforcing bands 9, 10, 11 and 12 in order that they may be suitably attached to the cylinder outlets. The preferable construction of the m'anifold is steel or' other suitable metal which is either- Welded or brazed so that it is of practically a unified Whole. of construction may be utilized, the main feature of the invention residing in. the fact that the sectional area of the manifold is of constantly increasing value and in the arrangement of the relative parts in such manner that suction will becreated in one part by the action of exhaust gases in the preceding parts. v

Although I have described the preferred embodiment of my invention, I do not limit myself thereto since various other forms of construction and materials may beused Without in any way departing from the spirit of the invention as set forth in the claims. 1 f

lVh-at claimed is:

1.-In combination Withaninternal combu'stion engine, an exhaust manifold comprising an outer conduit and an inner condult of expand1ng-d1ameters, and separate connections between the several motor cylin- However, other methods ders and the conduits alternately arranged whereby the suction created by one cylinder exhaust assists in the exhausting of the suc-' ceedingly firing cylinder. w c

2. In QOmblIlilblOIl'Wltll an internal combustion engine, a manifold comprising separate conduits of expanding diameter and 'duits and the severalmotor cylinders soarranged that the suction created by the pasassistin the passage of gases from a suc- "ceedingly firing cylinder.

4i. In a multi-cylmder internal combustionen 'ine in combination With a c linder sage of exhaust gases from one cylinder will bank, an exhaust manifold comprising a being arranged Within the other, connections leading from one of said conduits to a pair of non-adjacent cylinders, and connections leading from the other of said con duits to a pairof adjacent cylinders.

Intestimony whereof I hereunto affix my signature.

cHARLES- JKIRKHAM.

' pair of conduits of different diameters, one 

